You should be able to reinstall the packages via yum and be back in business. Your data (at least HDFS) should not have been removed in this process. yum will do this if the package you are trying to remove has dependencies. I believe there are command-line options to tell it to forget about the dependencies.

You should be able to reinstall the packages via yum and be back in business. Your data (at least HDFS) should not have been removed in this process. yum will do this if the package you are trying to remove has dependencies. I believe there are command-line options to tell it to forget about the dependencies.

Sorry to hear about the removal of other packages but Clint is exactly right. To pile on, zookeeper is a fairly fundamental component of the stack. For example, the hadoop package depends on zookeeper so removing zookeeper will remove hadoop and all other hadoop packages (which transitively depend on hadoop).

Like Clint said, the state is always stored on the system, so if you were to reinstall hadoop (and without doing any reformat of HDFS), you should be able to continue from where you left.